There is described a device for a release module for attaching a pipe string to a heave compensated, load bearing unit arranged on a floating installation, more particularly in that two or more hydraulic cylinder units form an extendable connection between the heave compensated, load bearing unit and a portion of the pipe string.
Working on a well, such as an oil or gas well, from a floating installation (in the following also called a rig), equipment led down into the well is as a rule connected to the rig via some form of heave compensator to prevent that well equipment moves in the vertical direction in line with the wave or current induced heave motion of the rig.
By using a so-called workover riser in combination with a top drive, the workover riser is suspended from the top drive via rigid suspension links (“bails). The top drive heave compensator thereby functions also as the workover riser heave compensator. To prevent the workover riser from being broken in case the heave compensator fails, a so-called “weak link” i.e. a weakened unit is interconnected in the suspension. This element is according to prior art often made with some sort of shear pin device which when it breaks frees the workover pipe from the top drive. The drawback with such devices is that partly heavy components may come loose and thereby fall down on the deck below hurting personnel being there.
Also in heave compensated suspensions of other types of pipe strings, failure in the connected heave compensator may create the same problems as described above.